#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
import getopt
import pgdb
from fileformat import read_actionlist, write_actionlist
from util import *

# connection = pgdb.connect(database='oysteini_pbb2',
#                           user='oysteini_pbb',
#                           password='lio5Aide',
#                           host='postgres.pvv.ntnu.no');

# c = connection.cursor()
# c.execute('SELECT * from book')
# print fetchall_dict(c)

q_list_books = \
    'SELECT isbn, book.id AS id, title, category, person.id AS person_id, ' \
    '       lastname, firstname ' \
    'FROM book ' \
    'LEFT JOIN bookperson ON book.isbn=bookperson.book ' \
    'LEFT JOIN person ON bookperson.person=person.id'
q_list_persons = \
    'SELECT person.id, person.firstname, person.lastname, ' \
    '       COUNT(bookperson.id) AS num_books ' \
    'FROM person LEFT JOIN bookperson ON person.id=bookperson.person ' \
    'GROUP BY person.id, person.firstname, person.lastname'
q_list_categories = \
    'SELECT category.id, category.name, ' \
    '       COUNT(book.isbn) AS num_books ' \
    'FROM category ' \
    'LEFT JOIN book ON category.id=book.category ' \
    'GROUP BY category.id, category.name'
q_persons_for_book = \
    'SELECT person.id, lastname, firstname, relation ' \
    'FROM person ' \
    'INNER JOIN bookperson ON person.id=bookperson.person ' \
    'WHERE bookperson.book=%(isbn)s'
q_books_for_person = \
    'SELECT isbn, title, relation ' \
    'FROM bookperson ' \
    'INNER JOIN book ON bookperson.book=book.isbn ' \
    'WHERE bookperson.person=%(id)s'
q_books_for_category = \
    'SELECT isbn, title ' \
    'FROM book ' \
    'WHERE category=%(id)s'

def connect_to_db():
    connection = pgdb.connect(database='oysteini_pbb2',
                              user='oysteini_pbb',
                              password='lio5Aide',
                              host='postgres.pvv.ntnu.no')
    return connection

def get_by_id(connection, id):
    c = connection.cursor()
    q_book = 'SELECT * FROM book WHERE isbn=%(id)s OR id=%(id)s'
    q_person = 'SELECT * FROM person WHERE id=%(id)s'
    q_cat = 'SELECT * FROM category WHERE id=%(id)s'
    for (typ,q) in [('book', q_book),
                    ('person', q_person),
                    ('category', q_cat)]:
        c.execute(q, {'id': id})
        if c.rowcount > 0:
            d = fetchone_dict(c)
            d['type'] = typ
            return d
    return None

def list_of_dicts_to_dict(lst, key_name, value_name):
    res = {}
    for d in lst:
        if d[key_name] in res:
            res[d[key_name]].append(d[value_name])
        else:
            res[d[key_name]] = [d[value_name]]
    return res

def get_persons_for_book(connection, isbn):
    c = connection.cursor()
    c.execute(q_persons_for_book, {'isbn': isbn})
    return fetchall_dict(c)

def get_books_for_person(connection, person_id):
    c = connection.cursor()
    c.execute(q_books_for_person, {'id': person_id})
    return fetchall_dict(c)

def get_books_for_category(connection, cat_id):
    c = connection.cursor()
    c.execute(q_books_for_category, {'id': cat_id})
    return fetchall_dict(c)

def show_book(book):
    s = ''
    if book['id']:
        s += 'book %s %s\n' % (book['isbn'], book['id'])
    else:
        s += 'book %s\n' % book['isbn']
    s += 'Title: %s\n' % book['title']
    if book['subtitle']:
    	s += 'Subtitle: %s\n' % book['subtitle']
    s += 'ISBN: %s\n' % book['isbn']
    s += 'Persons:\n'
    for bp in book['persons_data']:
        s += ' %s %s %s (%s)\n' % (bp['id'], bp['firstname'], bp['lastname'],
                                   bp['relation'])
    if len(book['persons_data']) == 0:
        s += ' (no persons associated with this book)\n'
    if book['series']:
        s += 'Part of series: %s %s\n' % (book['series'], book['series_title'])
    s += 'Category: %s\n' % book['category']
    if book['publisher']:
        s += 'Publisher: %s\n' % book['publisher']
    if book['published_year']:
        s += 'Published year: %s\n' % book['published_year']
    if book['edition']:
        s += 'Edition: %s\n' % book['edition']
    if book['pages']:
        s += 'Number of pages: %s\n' % book['pages']
    if book['description']:
    	s += ('Description:\n%s\n' %
              '\n'.join(map(lambda line: ' '+line,
                            book['description'].split('\n'))))
    return s

def show_person(person):
    s = 'person %s\n' % person['id']
    s += 'Name: %s %s\n' % (person['firstname'], person['lastname'])
    s += 'Books:\n'
    for book in person['books']:
        s += ' %-13s %s (%s)\n' % (book['isbn'], book['title'], book['relation'])
    if len(person['books']) == 0:
        s += ' (no books by this person)\n'
    return s

def show_category(cat):
    s = 'category %s\n' % cat['id']
    s += 'Name: %s\n' % cat['name']
    s += 'Books:\n'
    for book in cat['books']:
        s += ' %-13s %s\n' % (book['isbn'], book['title'])
    if len(cat['books']) == 0:
        s += ' (no books)\n'
    return s

def show(connection, ids, commit_format=False, tmp_file=False):
    objects = map(lambda id: get_by_id(connection, id), ids)
    for i in range(len(ids)):
        typ = objects[i]['type']
        if typ == 'book':
            persons = get_persons_for_book(connection, objects[i]['isbn'])
            objects[i]['persons'] = list_of_dicts_to_dict(persons, 'relation', 'id')
            objects[i]['persons_data'] = persons
        elif typ == 'person':
            books = get_books_for_person(connection, objects[i]['id'])
            objects[i]['books'] = books
        elif typ == 'category':
            books = get_books_for_category(connection, objects[i]['id'])
            objects[i]['books'] = books
        if not objects[i]:
            objects[i] = 'No object with id %s.\n' % ids[i]
        elif commit_format:
            objects[i]['action'] = 'edit-%s' % typ
        else:
            show_funs = {'book': show_book,
                         'person': show_person,
                         'category': show_category}
            show_fun = show_funs[objects[i]['type']]
            objects[i] = show_fun(objects[i])

    if commit_format:
        output = write_actionlist(objects)
    else:
        output = '\n'.join(objects)
    if tmp_file:
        filename = write_tmpfile('.'.join(ids), output)
        print filename
        return filename
    else:
        print output.strip()

def list_books(connection):
    c = connection.cursor()
    c.execute(q_list_books)
    #print fetchall_dict(c)
    s = ''
    last_isbn = None
    for i in xrange(c.rowcount):
        d = fetchone_dict(c)
        if d['isbn'] != last_isbn:
            if last_isbn != None:
                s += '\n'
            s += '%-13s %-10s %-40s' % (d['isbn'], str_or_empty(d['id']), d['title'])
            if d['person_id']:
                s += ' ' + d['person_id']
        else:
            s += ', ' + d['person_id']
        last_isbn = d['isbn']
    print s

def list_persons(connection):
    c = connection.cursor()
    c.execute(q_list_persons)
    for i in xrange(c.rowcount):
        person = fetchone_dict(c)
        print '%-5s %-30s %d books' % (person['id'],
                                       person['firstname']+' '+person['lastname'],
                                       person['num_books'])

def list_categories(connection):
    c = connection.cursor()
    c.execute(q_list_categories)
    for i in xrange(c.rowcount):
        cat = fetchone_dict(c)
        print '%-15s %-30s %d books' % (cat['id'], cat['name'], cat['num_books'])

def list_cmd(connection, what):
    funs = { 'book': list_books,
             'person': list_persons,
             'category': list_categories }
    fun = funs[what]
    fun(connection)

def search_book(connection, search_strings, search_description=False):
    c = connection.cursor()
    c.execute('SELECT * FROM book WHERE book.title LIKE %(search_strings)s', {"search_strings": '%' + search_strings[0] + '%'})
    for  i in xrange(c.rowcount):
        cat = fetchone_dict(c)
        print cat['title'] 

def search_person(connection, search_strings):
    pass

def commit(connection, filename=None):
    pass

def edit(connection, ids):
    pass

def map_cmd(connection, shelfname=None, category=None):
    pass

commands = { 'show':
                 { 'args': [('ids', (1,None))],
                   'options': ['commit_format', 'tmp_file'],
                   'fun': show,
                   'use_db': True },
             'list':
                 { 'args': [('what', (1,1))],
                   'options': [],
                   'fun': list_cmd,
                   'use_db': True },
             'search':
                 { 'args': [('search_strings', (1,None))],
                   'options': ['search_description'],
                   'fun': search_book,
                   'use_db': True },
             'search-person':
                 { 'args': [('search_strings', (1,None))],
                   'options': [],
                   'fun': search_person,
                   'use_db': True },
             'commit':
                 { 'args': [('filename', (0,1))],
                   'options': [],
                   'fun': commit,
                   'use_db': True },
             'edit':
                 { 'args': [('ids', (1,None))],
                   'options': [],
                   'fun': edit,
                   'use_db': True },
	     'map':
                 { 'args': [('shelfname', (0,1)), ('category', (0,1))],
                   'options': [],
                   'fun': map_cmd,
                   'use_db': True }
             }

flags = { 'commit_format':
          { 'help': 'output data in the format expected by the commit command' },
          'tmp_file':
          { 'help': 'output data to a new temporary file instead of to stdout' },
          'search_description':
          { 'help': 'include description field when searching' }
        }

general_options = [] # options applicable to all commands

class BadCommandLine(Exception):
    def __init__(self, msg):
        Exception.__init__(self, 'Bad command line: ' + msg)

def check_command_args(args, command):
    cmd_decl = commands[command]
    min_num_args = sum(map(lambda a: a[1][0], cmd_decl['args']))
    unlimited = any(map(lambda a: a[1][1] == None, cmd_decl['args']))
    if not unlimited:
        max_num_args = sum(map(lambda a: a[1][1], cmd_decl['args']))
    if len(args) < min_num_args:
        raise BadCommandLine('Too few arguments for command %s (expects at least %d, %d given).'
                             % (command, min_num_args, len(args)))
    if (not unlimited) and (len(args) > max_num_args):
        raise BadCommandLine('Too many arguments for command %s (expects at most %d, %d given).'
                             % (command, max_num_args, len(args)))

def check_command_opts(opts, command):
    cmd_decl = commands[command]
    for opt,val in opts:
        if ((opt not in cmd_decl['options']) and
            (opt not in general_options)):
            raise BadCommandLine('Option %s not applicable to command %s.'
                                 % (opt, command))

def assign_command_args(args, command):
    cmd_decl = commands[command]
    d = {}
    i = 0
    for param in cmd_decl['args']:
        pname = param[0]
        pmin = param[1][0]
        pmax = param[1][1]
        if pmax == 1:
            if i < len(args):
                d[pname] = args[i]
                i += 1
            else:
                d[pname] = None
        else:
            d[pname] = []
            j = 0
            while i + j < len(args) and (pmax == None or j < pmax):
                d[pname].append(args[i + j])
                j += 1
            i = i + j
    return d

def assign_command_opts(opts, command):
    d = {}
    for option, value in opts:
        if option in flags:
            d[option] = True
        else:
            d[option] = value
    return d

def parse_cmdline(args):
    def getopt_option_name(internal_name):
        return internal_name.replace('_', '-')
    def internal_option_name(getopt_ret_name):
        return getopt_ret_name[2:].replace('-', '_')

    option_names = map(getopt_option_name, flags)

    options, args = getopt.getopt(args, '', option_names)
    
    if len(args) == 0:
        raise BadCommandLine('No command specified.')
    cmd_name = args[0]
    if cmd_name not in commands:
        raise BadCommandLine('Nonexisting command %s.' % cmd_name)
    cmd_decl = commands[cmd_name]
    cmd_args = args[1:]
    cmd_opts = map(lambda (opt,val): (internal_option_name(opt), val),
                   options)

    check_command_args(cmd_args, cmd_name)
    check_command_opts(cmd_opts, cmd_name)

    return { 'command': cmd_name,
             'args': combine_dicts(assign_command_args(cmd_args, cmd_name),
                                   assign_command_opts(cmd_opts, cmd_name)) }

def invoke_command(command, args):
    cmd_decl = commands[command]
    cmd_decl['fun'](**args)

def main(argv):
    cmdline_parsed = parse_cmdline(argv[1:])
    #print 'command line parsed to:', cmdline_parsed
    command = cmdline_parsed['command']
    args = cmdline_parsed['args']
    if commands[cmdline_parsed['command']]['use_db']:
        connection = connect_to_db()
        args['connection'] = connection
    invoke_command(command, args)

if __name__ == "__main__":
    main(sys.argv)